Olive oil polyphenols may boost cognition: Nutrigenomic data

Supplementing the diet with olive oil polyphenols may beneficially affect gene expression linked to brain function, says a new nutrigenomic study from Italy.

Scientists from the Department of Neuroscience, Area Drug and Child Health (NEUROFARBA) at the University of Florence and Chiesi Pharmaceuticals report that extra virgin olive oil rich in polyphenols was associated with “strong” improvements in coordination, memory, and anxiety-related behavior in older lab mice.

The polyphenol-rich olive oil was found to change the expression of micro RNA (miRNA) – a small non-coding RNA molecule that plays a role in gene expression – and produce profiles similar to those observed in young mice, according to data published in the European Journal of Nutrition​​.

“In a nutraceutical perspective, the long-term treatment with olive oil phenols could become part of a neuroprotective strategy for the prevention of brain aging, mediated by the induction of health-promoting genes and the coordinated modulation of miRNA profiles,”​ wrote the authors, led by Dr Cristina Luceri.

Study details​

Dr Luceri and her co-workers used 10 month old (middle-aged) lab mice and supplemented their diets with either extra-virgin olive oil rich in phenols (718.8 mg of total phenols per kg of olive oil) or the same olive oil deprived of phenolics (9.3 mg of total phenols per kg of olive oil) for six months.

Results showed that, at the end of the study, the animals in the polyphenol-rich olive oil group performed significantly better in motor coordination tests compared with the other animals. Indeed, performance was improved by 74% compared to the low polyphenol olive oil group.

Anxiety-related behavior and spatial memory also improved in the high polyphenol olive oil group, said the researchers.

In terms of gene expression, the majority of the changes were observed in the cerebral cortex of the animals, an area of the brain linked to memory, attention, perception, awareness, and similar functions.

The polyphenol-rich olive oil was found to change the expression of miRNA in middle-aged mice and produce profiles similar to those observed in young animals.Image: iStockPhoto

The polyphenol-rich olive oil group displayed beneficial changes to genes modulated by aging, said the researchers, while the opposite was observed in the low-polyphenol group.

Significant differences in miRNA expression were also found between the two olive oil groups, with 63 miRNAs significantly down-regulated compared to mice in the olive oil deprived of phenolics group. (A total of 1,203 were analyzed.)

“We are among the first to report that a dietary intervention starting from middle age with food rich in phenols can modulate at the central level the expression of genes and miRNAs involved in neuronal function and synaptic plasticity, along with cognitive, motor and emotional behavior,” ​wrote the researchers.